forked from lix-project/lix
421 lines
14 KiB
C++
421 lines
14 KiB
C++
#pragma once
|
||
|
||
#include "attr-set.hh"
|
||
#include "value.hh"
|
||
#include "nixexpr.hh"
|
||
#include "symbol-table.hh"
|
||
#include "config.hh"
|
||
|
||
#include <regex>
|
||
#include <map>
|
||
#include <optional>
|
||
#include <unordered_map>
|
||
#include <mutex>
|
||
|
||
|
||
namespace nix {
|
||
|
||
|
||
class Store;
|
||
class EvalState;
|
||
class StorePath;
|
||
enum RepairFlag : bool;
|
||
|
||
|
||
typedef void (* PrimOpFun) (EvalState & state, const Pos & pos, Value * * args, Value & v);
|
||
|
||
|
||
struct PrimOp
|
||
{
|
||
PrimOpFun fun;
|
||
size_t arity;
|
||
Symbol name;
|
||
std::vector<std::string> args;
|
||
const char * doc = nullptr;
|
||
};
|
||
|
||
|
||
struct Env
|
||
{
|
||
Env * up;
|
||
unsigned short prevWith:14; // nr of levels up to next `with' environment
|
||
enum { Plain = 0, HasWithExpr, HasWithAttrs } type:2;
|
||
Value * values[0];
|
||
};
|
||
|
||
|
||
Value & mkString(Value & v, std::string_view s, const PathSet & context = PathSet());
|
||
|
||
void copyContext(const Value & v, PathSet & context);
|
||
|
||
|
||
/* Cache for calls to addToStore(); maps source paths to the store
|
||
paths. */
|
||
typedef std::map<Path, StorePath> SrcToStore;
|
||
|
||
|
||
std::ostream & operator << (std::ostream & str, const Value & v);
|
||
|
||
|
||
typedef std::pair<std::string, std::string> SearchPathElem;
|
||
typedef std::list<SearchPathElem> SearchPath;
|
||
|
||
|
||
/* Initialise the Boehm GC, if applicable. */
|
||
void initGC();
|
||
|
||
|
||
class EvalState
|
||
{
|
||
public:
|
||
SymbolTable symbols;
|
||
|
||
const Symbol sWith, sOutPath, sDrvPath, sType, sMeta, sName, sValue,
|
||
sSystem, sOverrides, sOutputs, sOutputName, sIgnoreNulls,
|
||
sFile, sLine, sColumn, sFunctor, sToString,
|
||
sRight, sWrong, sStructuredAttrs, sBuilder, sArgs,
|
||
sContentAddressed,
|
||
sOutputHash, sOutputHashAlgo, sOutputHashMode,
|
||
sRecurseForDerivations,
|
||
sDescription, sSelf, sEpsilon;
|
||
Symbol sDerivationNix;
|
||
|
||
/* If set, force copying files to the Nix store even if they
|
||
already exist there. */
|
||
RepairFlag repair;
|
||
|
||
/* The allowed filesystem paths in restricted or pure evaluation
|
||
mode. */
|
||
std::optional<PathSet> allowedPaths;
|
||
|
||
Value vEmptySet;
|
||
|
||
const ref<Store> store;
|
||
|
||
|
||
private:
|
||
SrcToStore srcToStore;
|
||
|
||
/* A cache from path names to parse trees. */
|
||
#if HAVE_BOEHMGC
|
||
typedef std::map<Path, Expr *, std::less<Path>, traceable_allocator<std::pair<const Path, Expr *> > > FileParseCache;
|
||
#else
|
||
typedef std::map<Path, Expr *> FileParseCache;
|
||
#endif
|
||
FileParseCache fileParseCache;
|
||
|
||
/* A cache from path names to values. */
|
||
#if HAVE_BOEHMGC
|
||
typedef std::map<Path, Value, std::less<Path>, traceable_allocator<std::pair<const Path, Value> > > FileEvalCache;
|
||
#else
|
||
typedef std::map<Path, Value> FileEvalCache;
|
||
#endif
|
||
FileEvalCache fileEvalCache;
|
||
|
||
SearchPath searchPath;
|
||
|
||
std::map<std::string, std::pair<bool, std::string>> searchPathResolved;
|
||
|
||
/* Cache used by checkSourcePath(). */
|
||
std::unordered_map<Path, Path> resolvedPaths;
|
||
|
||
/* Cache used by prim_match(). */
|
||
std::unordered_map<std::string, std::regex> regexCache;
|
||
|
||
public:
|
||
|
||
EvalState(const Strings & _searchPath, ref<Store> store);
|
||
~EvalState();
|
||
|
||
void addToSearchPath(const string & s);
|
||
|
||
SearchPath getSearchPath() { return searchPath; }
|
||
|
||
Path checkSourcePath(const Path & path);
|
||
|
||
void checkURI(const std::string & uri);
|
||
|
||
/* When using a diverted store and 'path' is in the Nix store, map
|
||
'path' to the diverted location (e.g. /nix/store/foo is mapped
|
||
to /home/alice/my-nix/nix/store/foo). However, this is only
|
||
done if the context is not empty, since otherwise we're
|
||
probably trying to read from the actual /nix/store. This is
|
||
intended to distinguish between import-from-derivation and
|
||
sources stored in the actual /nix/store. */
|
||
Path toRealPath(const Path & path, const PathSet & context);
|
||
|
||
/* Parse a Nix expression from the specified file. */
|
||
Expr * parseExprFromFile(const Path & path);
|
||
Expr * parseExprFromFile(const Path & path, StaticEnv & staticEnv);
|
||
|
||
/* Parse a Nix expression from the specified string. */
|
||
Expr * parseExprFromString(std::string_view s, const Path & basePath, StaticEnv & staticEnv);
|
||
Expr * parseExprFromString(std::string_view s, const Path & basePath);
|
||
|
||
Expr * parseStdin();
|
||
|
||
/* Evaluate an expression read from the given file to normal
|
||
form. Optionally enforce that the top-level expression is
|
||
trivial (i.e. doesn't require arbitrary computation). */
|
||
void evalFile(const Path & path, Value & v, bool mustBeTrivial = false);
|
||
|
||
void resetFileCache();
|
||
|
||
/* Look up a file in the search path. */
|
||
Path findFile(const string & path);
|
||
Path findFile(SearchPath & searchPath, const string & path, const Pos & pos = noPos);
|
||
|
||
/* If the specified search path element is a URI, download it. */
|
||
std::pair<bool, std::string> resolveSearchPathElem(const SearchPathElem & elem);
|
||
|
||
/* Evaluate an expression to normal form, storing the result in
|
||
value `v'. */
|
||
void eval(Expr * e, Value & v);
|
||
|
||
/* Evaluation the expression, then verify that it has the expected
|
||
type. */
|
||
inline bool evalBool(Env & env, Expr * e);
|
||
inline bool evalBool(Env & env, Expr * e, const Pos & pos);
|
||
inline void evalAttrs(Env & env, Expr * e, Value & v);
|
||
|
||
/* If `v' is a thunk, enter it and overwrite `v' with the result
|
||
of the evaluation of the thunk. If `v' is a delayed function
|
||
application, call the function and overwrite `v' with the
|
||
result. Otherwise, this is a no-op. */
|
||
inline void forceValue(Value & v, const Pos & pos = noPos);
|
||
|
||
/* Force a value, then recursively force list elements and
|
||
attributes. */
|
||
void forceValueDeep(Value & v);
|
||
|
||
/* Force `v', and then verify that it has the expected type. */
|
||
NixInt forceInt(Value & v, const Pos & pos);
|
||
NixFloat forceFloat(Value & v, const Pos & pos);
|
||
bool forceBool(Value & v, const Pos & pos);
|
||
inline void forceAttrs(Value & v);
|
||
inline void forceAttrs(Value & v, const Pos & pos);
|
||
inline void forceList(Value & v);
|
||
inline void forceList(Value & v, const Pos & pos);
|
||
void forceFunction(Value & v, const Pos & pos); // either lambda or primop
|
||
string forceString(Value & v, const Pos & pos = noPos);
|
||
string forceString(Value & v, PathSet & context, const Pos & pos = noPos);
|
||
string forceStringNoCtx(Value & v, const Pos & pos = noPos);
|
||
|
||
/* Return true iff the value `v' denotes a derivation (i.e. a
|
||
set with attribute `type = "derivation"'). */
|
||
bool isDerivation(Value & v);
|
||
|
||
std::optional<string> tryAttrsToString(const Pos & pos, Value & v,
|
||
PathSet & context, bool coerceMore = false, bool copyToStore = true);
|
||
|
||
/* String coercion. Converts strings, paths and derivations to a
|
||
string. If `coerceMore' is set, also converts nulls, integers,
|
||
booleans and lists to a string. If `copyToStore' is set,
|
||
referenced paths are copied to the Nix store as a side effect. */
|
||
string coerceToString(const Pos & pos, Value & v, PathSet & context,
|
||
bool coerceMore = false, bool copyToStore = true);
|
||
|
||
string copyPathToStore(PathSet & context, const Path & path);
|
||
|
||
/* Path coercion. Converts strings, paths and derivations to a
|
||
path. The result is guaranteed to be a canonicalised, absolute
|
||
path. Nothing is copied to the store. */
|
||
Path coerceToPath(const Pos & pos, Value & v, PathSet & context);
|
||
|
||
public:
|
||
|
||
/* The base environment, containing the builtin functions and
|
||
values. */
|
||
Env & baseEnv;
|
||
|
||
/* The same, but used during parsing to resolve variables. */
|
||
StaticEnv staticBaseEnv; // !!! should be private
|
||
|
||
private:
|
||
|
||
unsigned int baseEnvDispl = 0;
|
||
|
||
void createBaseEnv();
|
||
|
||
Value * addConstant(const string & name, Value & v);
|
||
|
||
Value * addPrimOp(const string & name,
|
||
size_t arity, PrimOpFun primOp);
|
||
|
||
Value * addPrimOp(PrimOp && primOp);
|
||
|
||
public:
|
||
|
||
Value & getBuiltin(const string & name);
|
||
|
||
private:
|
||
|
||
inline Value * lookupVar(Env * env, const ExprVar & var, bool noEval);
|
||
|
||
friend struct ExprVar;
|
||
friend struct ExprAttrs;
|
||
friend struct ExprLet;
|
||
|
||
Expr * parse(const char * text, FileOrigin origin, const Path & path,
|
||
const Path & basePath, StaticEnv & staticEnv);
|
||
|
||
public:
|
||
|
||
/* Do a deep equality test between two values. That is, list
|
||
elements and attributes are compared recursively. */
|
||
bool eqValues(Value & v1, Value & v2);
|
||
|
||
bool isFunctor(Value & fun);
|
||
|
||
void callFunction(Value & fun, Value & arg, Value & v, const Pos & pos);
|
||
void callPrimOp(Value & fun, Value & arg, Value & v, const Pos & pos);
|
||
|
||
/* Automatically call a function for which each argument has a
|
||
default value or has a binding in the `args' map. */
|
||
void autoCallFunction(Bindings & args, Value & fun, Value & res);
|
||
|
||
/* Allocation primitives. */
|
||
Value * allocValue();
|
||
Env & allocEnv(size_t size);
|
||
|
||
Value * allocAttr(Value & vAttrs, const Symbol & name);
|
||
Value * allocAttr(Value & vAttrs, const std::string & name);
|
||
|
||
Bindings * allocBindings(size_t capacity);
|
||
|
||
void mkList(Value & v, size_t length);
|
||
void mkAttrs(Value & v, size_t capacity);
|
||
void mkThunk_(Value & v, Expr * expr);
|
||
void mkPos(Value & v, Pos * pos);
|
||
|
||
void concatLists(Value & v, size_t nrLists, Value * * lists, const Pos & pos);
|
||
|
||
/* Print statistics. */
|
||
void printStats();
|
||
|
||
void realiseContext(const PathSet & context);
|
||
|
||
private:
|
||
|
||
unsigned long nrEnvs = 0;
|
||
unsigned long nrValuesInEnvs = 0;
|
||
unsigned long nrValues = 0;
|
||
unsigned long nrListElems = 0;
|
||
unsigned long nrAttrsets = 0;
|
||
unsigned long nrAttrsInAttrsets = 0;
|
||
unsigned long nrOpUpdates = 0;
|
||
unsigned long nrOpUpdateValuesCopied = 0;
|
||
unsigned long nrListConcats = 0;
|
||
unsigned long nrPrimOpCalls = 0;
|
||
unsigned long nrFunctionCalls = 0;
|
||
|
||
bool countCalls;
|
||
|
||
typedef std::map<Symbol, size_t> PrimOpCalls;
|
||
PrimOpCalls primOpCalls;
|
||
|
||
typedef std::map<ExprLambda *, size_t> FunctionCalls;
|
||
FunctionCalls functionCalls;
|
||
|
||
void incrFunctionCall(ExprLambda * fun);
|
||
|
||
typedef std::map<Pos, size_t> AttrSelects;
|
||
AttrSelects attrSelects;
|
||
|
||
friend struct ExprOpUpdate;
|
||
friend struct ExprOpConcatLists;
|
||
friend struct ExprSelect;
|
||
friend void prim_getAttr(EvalState & state, const Pos & pos, Value * * args, Value & v);
|
||
friend void prim_match(EvalState & state, const Pos & pos, Value * * args, Value & v);
|
||
};
|
||
|
||
|
||
/* Return a string representing the type of the value `v'. */
|
||
string showType(ValueType type);
|
||
string showType(const Value & v);
|
||
|
||
/* Decode a context string ‘!<name>!<path>’ into a pair <path,
|
||
name>. */
|
||
std::pair<string, string> decodeContext(std::string_view s);
|
||
|
||
/* If `path' refers to a directory, then append "/default.nix". */
|
||
Path resolveExprPath(Path path);
|
||
|
||
struct InvalidPathError : EvalError
|
||
{
|
||
Path path;
|
||
InvalidPathError(const Path & path);
|
||
#ifdef EXCEPTION_NEEDS_THROW_SPEC
|
||
~InvalidPathError() throw () { };
|
||
#endif
|
||
};
|
||
|
||
struct EvalSettings : Config
|
||
{
|
||
EvalSettings();
|
||
|
||
static Strings getDefaultNixPath();
|
||
|
||
Setting<bool> enableNativeCode{this, false, "allow-unsafe-native-code-during-evaluation",
|
||
"Whether builtin functions that allow executing native code should be enabled."};
|
||
|
||
Setting<Strings> nixPath{
|
||
this, getDefaultNixPath(), "nix-path",
|
||
"List of directories to be searched for `<...>` file references."};
|
||
|
||
Setting<bool> restrictEval{
|
||
this, false, "restrict-eval",
|
||
R"(
|
||
If set to `true`, the Nix evaluator will not allow access to any
|
||
files outside of the Nix search path (as set via the `NIX_PATH`
|
||
environment variable or the `-I` option), or to URIs outside of
|
||
`allowed-uri`. The default is `false`.
|
||
)"};
|
||
|
||
Setting<bool> pureEval{this, false, "pure-eval",
|
||
"Whether to restrict file system and network access to files specified by cryptographic hash."};
|
||
|
||
Setting<bool> enableImportFromDerivation{
|
||
this, true, "allow-import-from-derivation",
|
||
R"(
|
||
By default, Nix allows you to `import` from a derivation, allowing
|
||
building at evaluation time. With this option set to false, Nix will
|
||
throw an error when evaluating an expression that uses this feature,
|
||
allowing users to ensure their evaluation will not require any
|
||
builds to take place.
|
||
)"};
|
||
|
||
Setting<Strings> allowedUris{this, {}, "allowed-uris",
|
||
R"(
|
||
A list of URI prefixes to which access is allowed in restricted
|
||
evaluation mode. For example, when set to
|
||
`https://github.com/NixOS`, builtin functions such as `fetchGit` are
|
||
allowed to access `https://github.com/NixOS/patchelf.git`.
|
||
)"};
|
||
|
||
Setting<bool> traceFunctionCalls{this, false, "trace-function-calls",
|
||
R"(
|
||
If set to `true`, the Nix evaluator will trace every function call.
|
||
Nix will print a log message at the "vomit" level for every function
|
||
entrance and function exit.
|
||
|
||
function-trace entered undefined position at 1565795816999559622
|
||
function-trace exited undefined position at 1565795816999581277
|
||
function-trace entered /nix/store/.../example.nix:226:41 at 1565795253249935150
|
||
function-trace exited /nix/store/.../example.nix:226:41 at 1565795253249941684
|
||
|
||
The `undefined position` means the function call is a builtin.
|
||
|
||
Use the `contrib/stack-collapse.py` script distributed with the Nix
|
||
source code to convert the trace logs in to a format suitable for
|
||
`flamegraph.pl`.
|
||
)"};
|
||
|
||
Setting<bool> useEvalCache{this, true, "eval-cache",
|
||
"Whether to use the flake evaluation cache."};
|
||
};
|
||
|
||
extern EvalSettings evalSettings;
|
||
|
||
}
|